Central processing unit resource allocation method and computing node

ABSTRACT

A method for allocating a central processing unit resource to a virtual machine, including determining, according to a change in the number of virtual machines in an advanced resource pool, the number of allocated physical cores in the advanced resource pool; and adjusting, according to the number of the allocated physical cores in the advanced resource pool, the number of allocated physical cores in a default resource pool, where the advanced resource pool and the default resource pool are resource pools that are obtained by dividing physical cores of a central processing unit according to service levels of the resource pools.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Ser. No. 14/516,936, filed onOct. 17, 2014, which is a continuation of International Application No.PCT/CN2012/080872, filed on Aug. 31, 2012, Both of the aforementionedapplications are hereby incorporated by reference in their entireties.

TECHNICAL FIELD

Embodiments of the present invention relate to virtualizationtechnologies, and in particular, to a central processing unit resourceallocation method and a computing node.

BACKGROUND

Currently, virtualization technologies are widely applied in the fieldof information technologies. A virtualization technology provides acapability of deploying a plurality of virtual machines onto one server,which reduces overall costs of a user and improves reliability andflexibility of applications. Currently, CPU overcommitment isuniversally implemented for management of central processing units(CPUs) of virtual machines in the industry, that is, the number ofvirtual CPUs of virtual machines is larger than the number of physicalCPUs in a server, to fully use physical resources. However, in a case inwhich physical resources are short, how to allocate physical CPUresources appropriately becomes one of the biggest problems that areencountered. A commonly used implementation manner is to set prioritiesfor the virtual machines, and allocate different quotas of CPU resourcesto the virtual machines according to different priorities. A higherquota of physical CPU resources is allocated to a virtual machine of ahigher priority, to provide different service for users with differentrequirements and improve quality of service.

Because physical CPU resources are allocated to virtual machinesaccording to priorities, a virtual machine of a higher priority mayoccupy a dominant position and a virtual machine of a lower priority isunable to obtain a physical CPU resource, which is adverse to effectiveallocation of the physical CPU resources.

SUMMARY

Embodiments of the present invention propose a central processing unitresource allocation method. It is implemented by separating physicalcores of a CPU into different resource pools that, the physical coresare isolated between different resource pools, and the physical coresare allocated dynamically between different resource pools according tothe number of virtual machines served by each resource pool, therebyimplementing efficient use of the physical core resources and reliablyensuring quality of service of virtual machines in different resourcepools.

According to a first aspect, a central processing unit resourceallocation method is proposed, where the method includes:

adjusting dynamically, according to a change in the number of virtualmachines in an advanced resource pool, the number of allocated physicalcores in the advanced resource pool; and

adjusting, according to the number of the allocated physical cores inthe advanced resource pool, the number of allocated physical cores in adefault resource pool,

where the advanced resource pool and the default resource pool areresource pools that are obtained by dividing physical cores of a centralprocessing unit according to service levels of the resource pools.

With reference to the first aspect, in a first possible implementationmanner, the service level includes the number of physical core computingresources that can be occupied by each virtual machine.

With reference to the first aspect or the first possible implementationmanner of the first aspect, in a second possible implementation manner,virtual machines in the default resource pool share computing resourcesof all the physical cores in the default resource pool.

With reference to the first aspect or the first or second possibleimplementation manner of the first aspect, in a third possibleimplementation manner, the advanced resource pool includes a level-1resource pool, where each virtual machine in the level-1 resource poolis allowed to exclusively occupy one physical core computing resource.

With reference to the first aspect or any one of the first to thirdpossible implementation manners of the first aspect, in a fourthpossible implementation manner, the advanced resource pool includes alevel-2 resource pool, where each virtual machine in the level-2resource pool is allowed to occupy 50% of one physical core computingresource.

With reference to the first aspect or any one of the first to fourthpossible implementation manners of the first aspect, in a fifth possibleimplementation manner, the adjusting dynamically, according to a changein the number of virtual machines in an advanced resource pool, thenumber of allocated physical cores in the advanced resource poolincludes:

when the number of the virtual machines in the advanced resource poolincreases, determining, according to the number of increased virtualmachines and a service level of the advanced resource pool, a firstnumber of physical cores that need to be allocated to the advancedresource pool; and

allocating the first number of physical cores to the advanced resourcepool from the default resource pool;

or

when the number of the virtual machines in the advanced resource pooldecreases, determining, according to the number of decreased virtualmachines and a service level of the advanced resource pool, a secondnumber of physical cores that need to be subtracted from the advancedresource pool; and

allocating the second number of physical cores to the default resourcepool from the advanced resource pool.

With reference to the first aspect or any one of the first to fifthpossible implementation manners of the first aspect, in a sixth possibleimplementation manner, the determining, according to the number ofdecreased virtual machines and a service level of the advanced resourcepool when the number of the virtual machines in the advanced resourcepool decreases, a second number of physical cores that need to besubtracted from the advanced resource pool, and allocating the secondnumber of physical cores to the default resource pool from the advancedresource pool, specifically includes: allocating the physical cores inthe advanced resource pool to the default resource pool when no virtualmachine runs in the advanced resource pool.

With reference to the first aspect or any one of the first to sixthpossible implementation manners of the first aspect, in a seventhpossible implementation manner, before the adjusting dynamically,according to a change in the number of virtual machines in an advancedresource pool, the number of allocated physical cores in the advancedresource pool, the method further includes:

determining that, after the number of the virtual machines in theadvanced resource pool changes, the number of the physical cores in theadvanced resource pool is insufficient to satisfy the service level ofthe advanced resource pool.

With reference to the first aspect or any one of the first to sixthpossible implementation manners of the first aspect, in an eighthpossible implementation manner, before the adjusting dynamically,according to a change in the number of virtual machines in an advancedresource pool, the number of allocated physical cores in the advancedresource pool,

the method further includes:

determining that, after the number of the virtual machines in theadvanced resource pool changes, at least one idle physical corecomputing resource that does not serve a virtual machine in the advancedresource pool exists in the advanced resource pool.

With reference to the first aspect or any one of the first to eighthpossible implementation manners of the first aspect, in a ninth possibleimplementation manner, the method further includes: setting, for thevirtual machines in the default resource pool, an upper-limit percentageand/or a lower-limit percentage of the physical core computing resourcesthat can be occupied by each virtual machine.

With reference to the first aspect or any one of the first to ninthpossible implementation manners of the first aspect, in a tenth possibleimplementation manner, the method further includes: setting, for thevirtual machines in the default resource pool, a priority of eachvirtual machine in using physical core computing resources, andallocating physical core computing resources to the virtual machines inthe default resource pool in descending order of priorities.

According to a second aspect, a computing node applicable to a virtualsystem is proposed, where the computing node includes:

a resource adjusting unit, configured to adjust dynamically, accordingto a change in the number of virtual machines in an advanced resourcepool, the number of allocated physical cores in the advanced resourcepool, and adjust, according to the number of the allocated physicalcores in the advanced resource pool, the number of allocated physicalcores in a default resource pool; and

a resource allocating unit, configured to divide physical cores of acentral processing unit into the default resource pool and the advancedresource pool according to service levels of the resource pools.

With reference to the second aspect, in a first possible implementationmanner, when the number of the virtual machines in the advanced resourcepool increases, the resource adjusting unit determines, according to thenumber of increased virtual machines and a service level of the advancedresource pool, a first number of physical cores that need to beallocated to the advanced resource pool, and allocates the first numberof physical cores to the advanced resource pool from the defaultresource pool;

or

when the number of the virtual machines in the advanced resource pooldecreases, the resource adjusting unit determines, according to thenumber of decreased virtual machines and a service level of the advancedresource pool, a second number of physical cores that need to besubtracted from the advanced resource pool, and allocates the secondnumber of physical cores to the default resource pool from the advancedresource pool.

With reference to the second aspect or the first possible implementationmanner of the second aspect, in a second possible implementation manner,the computing node further includes:

a first determining unit, configured to determine that, after the numberof the virtual machines in the advanced resource pool changes, thenumber of the physical cores in the advanced resource pool isinsufficient to satisfy the service level of the advanced resource pool.

With reference to the second aspect or the first possible implementationmanner of the second aspect, in a third possible implementation manner,the computing node further includes: a first determining unit,configured to determine that, when the number of the virtual machines inthe advanced resource pool changes, at least one idle physical corecomputing resource that does not serve a virtual machine in the advancedresource pool exists in the advanced resource pool.

With reference to the second aspect or any one of the first to thirdpossible implementation manners of the second aspect, in a fourthpossible implementation manner, the resource allocating unit isconfigured to set, for each virtual machine in the default resourcepool, an upper-limit percentage and/or a lower-limit percentage of thephysical core computing resources that can be occupied by each virtualmachine.

With reference to the second aspect or any one of the first to fourthpossible implementation manners of the second aspect, in a fifthpossible implementation manner, the resource allocating unit isconfigured to set, for the virtual machines in the default resourcepool, a priority of each virtual machine in using physical corecomputing resources, and allocate physical core computing resources tothe virtual machines in the default resource pool in descending order ofpriorities.

According to the embodiments of the present invention, physical coresare divided into different resource pools, and computing resources ofphysical cores in one resource pool are isolated from those in anotherresource pool, thereby implementing effective allocation of physicalcore computing resources for different application scenarios, avoidingappearance of a dominant virtual machine that occupies plenty ofcomputing resources for a long time, preventing imbalanced allocation ofphysical core computing resources, and improving efficiency of usingcomputing resources of the physical cores.

BRIEF DESCRIPTION OF THE DRAWINGS

To describe the technical solutions in the embodiments of the presentinvention more clearly, the following briefly introduces theaccompanying drawings required for describing the embodiments.Apparently, the accompanying drawings in the following description showmerely some embodiments of the present invention, and a person ofordinary skill in the art may still derive other drawings from theseaccompanying drawings without creative efforts.

FIG. 1 is a schematic flowchart of a central processing unit resourceallocation method according to an embodiment of the present invention;

FIG. 2 is a flowchart of a specific example a process of migrating avirtual machine into a resource pool according to an embodiment of thepresent invention;

FIG. 3 is a flowchart of a specific example of a process of migrating avirtual machine out of a resource pool according to an embodiment of thepresent invention;

FIG. 4 is signaling interworking diagram for migrating a virtual machinefrom a source computing node to a destination computing node;

FIG. 5 is a schematic structural diagram of a computing node accordingto an embodiment of the present invention;

FIG. 6 is a schematic structural diagram of a computing node accordingto an embodiment of the present invention; and

FIG. 7 is another schematic structural diagram of a computing nodeaccording to an embodiment of the present invention.

DETAILED DESCRIPTION

The following clearly describes the technical solutions in theembodiments of the present invention with reference to the accompanyingdrawings in the embodiments of the present invention. Apparently, thedescribed embodiments are a part rather than all of the embodiments ofthe present invention. All other embodiments obtained by a person ofordinary skill in the art based on the embodiments of the presentinvention without creative efforts shall fall within the protectionscope of the present invention.

The technical solutions in the embodiments of the present invention areimplemented based on a basic capability of binding a virtual CPU (VCPU)of a virtual machine to a specified resource pool. Persons skilled inthe art can understand specific manners and implementation methods forbinding a VCPU to a resource pool, which, for brevity, are not detailedherein.

In description of the embodiments of the present invention, a physicalcore refers to a core of a physical central processing unit. A server ora computing node on which a virtual machine runs generally includes aplurality of CPUs, and each CPU includes at least one physical core. Thephysical cores may be used for different purposes. In the embodiments ofthe present invention, CPU physical cores that form a resource pool maybe physical cores of one CPU or may be physical cores of a plurality ofCPUs, where the CPUs may be located on one server or computing node ormay be located on a plurality of servers or computing nodes, which isnot specifically limited in the embodiments of the present invention.

In the embodiments of the present invention, a virtual machine mayinclude a plurality of VCPUs. For ease of description, an example inwhich one virtual machine includes one VCPU is described. In thedescription process, because one virtual machine includes one VCPU inthe embodiments, “binding a VCPU and a resource pool” may also begenerally expressed by “binding a virtual machine and a resource pool”.Persons skilled in the art understand that the meaning of “binding”herein is the same as how the term is usually understood in the art.Persons skilled in the art can understand that “a virtual machine runsin a resource pool” means that the virtual machine occupies a physicalcore computing resource in the resource pool instead of occupying aphysical core computing resource in another resource pool. In theembodiments of the present invention, a physical core computing resourcerefers to a computing capability provided by the physical core.Computing resources that can be occupied by a virtual machine running ina resource pool may come from one physical core of the resource pool, ormay come from a plurality of physical cores in the resource pool, whichis not limited in the embodiments of the present invention. The“physical core computing resources that can be occupied by a virtualmachine” refer to physical core computing resources in the resource poolin which one virtual machine runs that can be occupied by the virtualmachine, or may refer to physical core computing resources in theresource pool in which the virtual machine runs that can be occupied byone VCPU of the virtual machine, or may refer to physical core computingresources in the resource pool in which the virtual machine runs thatcan be occupied by all VCPUs of the virtual machine. For clarity in thefollowing description, the embodiments of the present invention aredescribed by using an example in which the “physical core computingresources occupied by a virtual machine” are the physical core computingresources in the resource pool in which the virtual machine runs thatare occupied by all VCPUs of the virtual machine.

FIG. 1 is a schematic flowchart of a central processing unit resourceallocation method according to an embodiment of the present invention.As shown in FIG. 1, the method 100 includes the following steps:

110. Adjust dynamically, according to a change in the number of virtualmachines in an advanced resource pool, the number of allocated physicalcores in the advanced resource pool.

120. Adjust, according to the number of the allocated physical cores inthe advanced resource pool, the number of allocated physical cores in adefault resource pool, where

the advanced resource pool and the default resource pool are resourcepools that are obtained by dividing physical cores of a centralprocessing unit according to service levels of the resource pools.

In the embodiment of the present invention, each resource pool servesvirtual machines that run in the resource pool, and a service level ofthe resource pool corresponds to a service level required by the virtualmachines that run in the resource pool. The “service level” here is, forexample, the number of physical core computing resources that can beoccupied by each virtual machine. In this embodiment and subsequentembodiments of the present invention, “occupy” refers to physical corecomputing resources that are actually allocated to each virtual machinein the resource pool. For example, in an advanced resource pool, avirtual machine is allowed to occupy 50% of one physical core computingresource, which means that 50% of one physical core computing resourceis actually allocated to the virtual machine in the advanced resourcepool. For example, in another advanced resource pool, a virtual machineis allowed to occupy one physical core computing resource, which meansthat one physical core computing resource is actually allocated to onevirtual machine.

In the embodiment of the present invention, different resource pools arelogically isolated from each other. That is, the physical cores in eachresource pool serve only virtual machines that run in the resource pool,and provide physical core computing resources for the virtual machinesthat run in the resource pool. Logical isolation described here does notexclude a possibility of physical isolation. In a possibleimplementation manner according to the embodiment of the presentinvention, different resource pools may even be isolated from each otherphysically. For example, physical cores in different resource pools areinstalled on different computing nodes.

In the embodiment of the present invention, virtual machines that run inthe default resource pool share computing resources of all the physicalcores in the default resource pool. The advanced resource pool may beset according to a specific application requirement. In a possibleimplementation manner, the advanced resource pool includes a level-1resource pool, where each virtual machine in the level-1 resource poolis allowed to exclusively occupy one physical core computing resource,that is, a service level of the level-1 resource pool is 100%. In a casein which a virtual machine includes only one VCPU, the number ofphysical cores in the level-1 resource pool is equal to the number ofthe virtual machines that run in the resource pool. The level-1 resourcepool can ensure that one physical core computing resource is actuallyallocated to a virtual machine that always runs in the level-1 resourcepool, but the “one physical core computing resource” may come from oneor more physical cores in the resource pool. In another possibleimplementation manner, in addition to a level-1 resource pool, theadvanced resource pool also includes a level-2 resource pool. A virtualmachine that runs in the level-2 resource pool is allowed to occupy 50%of one physical core computing resource, that is, a service level of thelevel-2 resource pool is 50%. In other words, in the level-2 resourcepool, 50% of one physical core computing resource is actually allocatedto each virtual machine, but the “50% of one physical core computingresource” may come from one or more physical cores in the resource pool.In another possible implementation manner according to the embodiment ofthe present invention, the advanced resource pool may include only alevel-2 resource pool. In another possible implementation manneraccording to the embodiment of the present invention, the advancedresource pool may further include a level-3 resource pool, where avirtual machine that runs in the level-3 resource pool is allowed tooccupy 33% of one physical core computing resource. Persons skilled inthe art can understand that, depending on a specific applicationrequirement, more or fewer sub-resource pools may be set in the advancedresource pool, and service levels of the sub-resource pools may bedifferent.

According to the embodiment of the present invention, step 110 mayspecifically include:

when the number of the virtual machines in the advanced resource poolincreases, determining, according to the number of increased virtualmachines and a service level of the advanced resource pool, a firstnumber of physical cores that need to be allocated to the advancedresource pool; and

allocating the first number of physical cores to the advanced resourcepool from the default resource pool;

or

when the number of the virtual machines in the advanced resource pooldecreases, determining, according to the number of decreased virtualmachines and a service level of the advanced resource pool, a secondnumber of physical cores that need to be subtracted from the advancedresource pool; and

allocating the second number of physical cores to the default resourcepool from the advanced resource pool.

The physical cores in the advanced resource pool are allocated to thedefault resource pool when no virtual machine runs in the advancedresource pool. The following uses an example in which resource poolsinclude a default resource pool and an advanced resource pool, and theadvanced resource pool includes a level-1 resource pool and a level-2resource pool for description. It should be noted that the example usedhere are merely intended to describe implementation manners of theembodiment of the present invention, instead of limiting the embodimentof the present invention. In description of the embodiment of thepresent invention, virtual machines that run in resource pools ofdifferent service levels may also be called virtual machines ofcorresponding service levels. For example, a virtual machine that runsin the level-1 resource pool may be called a level-1 virtual machine,and a virtual machine that runs in the default resource pool may becalled a default virtual machine.

Initially, for example, after a system is powered on, all physicalresources are allocated to the default resource pool because no virtualmachine runs in the advanced resource pool. Depending on differentapplication scenarios, virtual machines are started and added todifferent resource pools or virtual machines are migrated into differentresource pools. A reverse process is to shut down the virtual machinesor migrate the virtual machines out of the resource pools. For example,a level-1 virtual machine, that is, a virtual machine allowed to occupy100% of one physical core computing resource is required. Then, alevel-1 virtual machine needs to be created in the level-1 resourcepool. Persons skilled in the art understand and know processes ofcreating and starting a virtual machine, and therefore, for brevity, theprocesses are not detailed herein. When level-1 virtual machines areadded to the level-1 resource pool, a first number of physical coresthat need to be allocated to the level-1 resource pool are determinedaccording to the number of the added level-1 virtual machines, and thenthe first number of physical cores are allocated to the level-1 resourcepool from the default resource pool. If the number of level-1 virtualmachines needs to be decreased according to a specific applicationscenario, for example, if a second number of level-1 virtual machinesneed to be migrated out of the level-1 resource pool or a second numberof level-1 virtual machines need to be shut down, by using an example inwhich the second number of level-1 virtual machines are migrated out ofthe level-1 resource pool, it is determined that the second number ofphysical cores need to be subtracted from the level-1 resource poolwhile the second number of level-1 virtual machines are migrated out ofthe level-1 resource pool. Subsequently, the second number of physicalcores in the level-1 resource pool are allocated to the default resourcepool. In this way, the number of allocated physical cores in the level-1resource pool is adjusted dynamically according to the change in thenumber of virtual machines in the level-1 resource pool, and the numberof allocated physical cores in the default resource pool is adjustedcorrespondingly.

For the level-2 resource pool, the adjusting manner is similar. Adifference is that 50% of one physical core computing resource isactually allocated to a level-2 virtual machine in the level-2 resourcepool.

According to the embodiment of the present invention, in a possibleimplementation manner, before step 110, the method further includes:

determining that, after the number of the virtual machines in theadvanced resource pool changes, the number of the physical cores in theadvanced resource pool is insufficient to satisfy a computing resourcerequirement of the advanced resource pool. For example, when one level-1virtual machine is added to the level-1 resource pool of the advancedresource pool, the level-1 resource pool is unable to satisfy computingresource requirements of all the virtual machines in the level-1resource pool because each virtual machine in the level-1 resource poolis allowed to exclusively occupy one physical core computing resource.The following case may also exist. For example, three level-2 virtualmachines exist in the level-2 resource pool of the advanced resourcepool, and each level-2 virtual machine is allowed to occupy 50% of onephysical core computing resource. Therefore, two physical cores need tobe allocated to the three level-2 virtual machines in the level-2resource pool. However, after the physical core computing resources areactually allocated to the three level-2 virtual machines, 50% of onephysical core computing resource is left. In this case, if one level-2virtual machine is added to the level-2 resource pool, it will not occurthat the level-2 resource pool is unable to satisfy the computingresource requirements of all the level-2 virtual machines. In this way,the remaining 50% of one physical core computing resource in the level-2resource pool may be allocated to the newly added virtual machine. Inthis case, it is unnecessary to allocate a new physical core to thelevel-2 resource pool from the default resource pool.

According to the embodiment of the present invention, in a possibleimplementation manner, after step 110, the method further includes:

determining that, after the number of the virtual machines in theadvanced resource pool changes, at least one idle physical corecomputing resource that does not serve a virtual machine in the advancedresource pool exists in the advanced resource pool, where the “at leastone idle physical core computing resource” may come from differentphysical cores, that is, a sum of computing resources from differentphysical cores is equivalent to one physical core computing resource.For example, after one level-1 virtual machine is migrated out of thelevel-1 resource pool of the advanced resource pool, one idle physicalcore computing resource appears in the level-1 resource pool. In thiscase, one physical core may be allocated to the default resource poolfrom the level-1 resource pool for use by a virtual machine that runs inthe default resource pool, so that computing resources of the physicalcore can be used efficiently.

For example, after one level-2 virtual machine is migrated out of thelevel-2 resource pool of the advanced resource pool, it is possible thatno idle physical core computing resource appears because each virtualmachine in the level-2 resource pool is allowed to occupy 50% of onephysical core computing resource. Therefore, only when it is determinedthat at least one idle physical core computing resource exists in thelevel-2 resource pool can the physical core be allocated back to thedefault resource pool from the level-2 resource pool.

As mentioned above, default virtual machines in the default resourcepool share computing resources of all the physical cores in the defaultresource pool. According to the embodiment of the present invention, asharing manner may be determined according to a specific condition. In afirst possible implementation manner, the default virtual machines mayevenly share computing resources of all the physical cores in thedefault resource pool. According to an improved solution based on thefirst possible implementation manner, an upper-limit percentage ofphysical core computing resources that can be occupied by each defaultvirtual machine in the default resource pool may be set. For example,the upper-limit percentage of the physical core computing resources thatcan be occupied by each virtual machine in the default resource pool are10% of one physical core computing resource. In this way, a dominantvirtual machine, that is, a virtual machine that occupies plenty ofcomputing resources, is prevented from appearing in the default resourcepool. According to another improved solution, to ensure computingperformance of the virtual machines in the default resource pool, alower-limit percentage of the physical core computing resources that canbe occupied by each virtual machine may be set. For example, thelower-limit percentage of the physical core computing resources that canbe occupied by each virtual machine in the default resource pool are 5%of one physical core computing resource. After the upper-limitpercentage and the lower-limit percentage of a physical core computingresource that can be occupied by each virtual machine are determined,before step 110 is performed, the method 100 includes:

determining, according to the number of the virtual machines in thedefault resource pool and the lower-limit percentage of the physicalcore computing resources that can be occupied by a virtual machine inthe default resource pool, that the default resource pool has sufficientresources to be allocated to the advanced resource pool; or, in a casein which a virtual machine is added to the default resource pool,determining that an upper limit of a capacity of the default resourcepool has not been reached, that is, an additional virtual machine canstill be accommodated.

For example, it is assumed that the lower-limit percentage of thephysical core computing resources that can be occupied by each virtualmachine in the default resource pool is 5%, and the upper-limitpercentage of the physical core computing resources that can be occupiedby each virtual machine in the default resource pool is 10%. In thiscase, it is assumed that the default resource pool includes 10 physicalcores, and then, in the default resource pool, physical core computingresources can be provided for a maximum of 200 default virtual machines,and physical core computing resources can be provided for at least 100default virtual machines. It is assumed that the number of the virtualmachines that run in the default resource pool is 185. If one level-1virtual machine needs to be added, that is, one physical core needs tobe allocated to the level-1 resource pool of the advanced resource poolfrom the default resource pool, according to a computation result, afterone physical core is allocated to the level-1 resource pool, theremaining physical core computing resources in the default resource poolcan provide physical core computing resources for a maximum of 180default virtual machines. However, 185 default virtual machines arerunning in the default resource pool currently. In this case, the method100 includes: rejecting a request for adding an advanced virtualmachine. In this example, the adding of a level-1 virtual machine isrejected. Certainly, in another case of the embodiment of the presentinvention, one physical core may be allocated to the level-1 resourcepool of the advanced resource pool, and a lower limit of physical corecomputing resources occupied by each default virtual machine in thedefault resource pool is adjusted, or, according to a deployment policyof virtual machines in the default resource pool, a correspondingdefault virtual machine is shut down to satisfy the existing lower limitof the physical core computing resources occupied by each defaultvirtual machine in the default resource pool.

For another example, it is assumed that the lower-limit percentage ofone physical core computing resource that can be occupied by eachvirtual machine in the default resource pool is 5%, and the upper-limitpercentage of one physical core computing resource that can be occupiedby each virtual machine in the default resource pool is 10%. In thiscase, it is assumed that the default resource pool includes 10 physicalcores, and the number of the virtual machines that run in the defaultresource pool is 185. If one virtual machine needs to be added to thedefault resource pool, that is, one default virtual machine needs to beadded, according to a computation result, the default resource pool canaccommodate three more default virtual machines, and therefore it isallowed to add one virtual machine to the default resource pool.

In another possible implementation manner, a priority may further be setfor a default virtual machine in the default resource pool. The physicalcore computing resources in the default resource pool preferentiallysatisfy a requirement of a default virtual machine of a high priority.Because the upper-limit percentage and the upper limit of the physicalcore computing resources that can be occupied by each default virtualmachine are set, the default virtual machine of a high priority will notbecome a “dominant virtual machine” that causes failure to allocate acomputing resource be to a default virtual machine of a low priority.

The following uses a specific procedure instance of adding a virtualmachine to a level-2 resource pool to describe an implementation processof the embodiment of the present invention. FIG. 2 is a flowchart of aspecific example of a virtual machine migration-in process according toan embodiment of the present invention. As shown in FIG. 2, a procedure200 of adding a virtual machine to a level-2 resource pool includes thefollowing steps:

210. A user requests migration of a virtual machine 1 into the level-2resource pool.

220. A system determines whether physical core computing resources aresufficient.

That is, according to the number of virtual machines in a level-1resource pool and the number of virtual machines in the level-2 resourcepool, the number of virtual machines in a default resource pool, and alower-limit percentage of computing resources allocated to each virtualmachine in the default resource pool, the system determines whetherthere are sufficient computing resources to be allocated to the level-2resource pool, where the level-1 resource pool and the level-2 resourcepool are included in an advanced resource pool of an advanced resourcepool currently. In this example, because a physical core may be migratedinto the level-2 resource pool, the system needs to determine that atleast one physical core in the default resource pool can be allocated tothe level-2 resource pool. If physical core resources are sufficient,the procedure proceeds to step 230; and, if physical core resources areinsufficient, the procedure skips to step 270.

230. If physical core computing resources are sufficient, the systemdetermines whether a new physical core needs to be allocated to thelevel-2 resource pool after the virtual machine 1 is migrated into thelevel-2 resource pool.

Each virtual machine in the level-2 resource pool is allowed to occupy50% of one physical core computing resource. Therefore, before thevirtual machine 1 is migrated into the level-2 resource pool, if thenumber of the virtual machines in the level-2 resource pool is an oddnumber, 50% computing resource of one physical core remain unallocatedin the level-2 resource pool. In this case, it is unnecessary toallocate a new physical core to the level-2 resource pool. On thecontrary, before the virtual machine 1 is migrated into the level-2resource pool, if the number of the virtual machines in the level-2resource pool is an even number, a physical core needs to be allocatedto the level-2 resource pool from the default resource pool so that thevirtual machine 1 is provided with a computing resource.

240. If it is unnecessary to allocate a new physical core to the level-2resource pool, migrate the virtual machine 1 into the level-2 resourcepool, and allocate the remaining 50% of one physical core computingresource to the virtual machine 1.

250. If it is necessary to allocate a new physical core to the level-2resource pool, allocate one physical core to the level-2 resource poolfrom the default resource pool, migrate the virtual machine 1 into thelevel-2 resource pool, and provide the virtual machine 1 with theremaining 50% of one physical core computing resource.

260. The default resource pool adjusts allocation of physical corecomputing resources among virtual machines in the default resource poolcorrespondingly.

According to the foregoing content, an adjustment manner of the physicalcore computing resources in the default resource pool varies withspecific settings of the default resource pool. For example, if thevirtual machines in the default resource pool evenly share computingresources of physical cores in the default resource pool, because aphysical core is subtracted, computing resources of a physical core thatare actually allocated to each virtual machine in the default resourcepool are reduced correspondingly.

270. The virtual machine 1 is not allowed to migrate into the level-2resource pool.

In this case, a notification may be sent to the user by using a message,indicating that the virtual machine 1 is not allowed to migrate into thelevel-2 resource pool because the physical core computing resources inthe system are insufficient.

The procedure of migrating a virtual machine into the level-1 resourcepool or the default resource pool is similar to the procedure shown inFIG. 2.

Corresponding to the procedure shown in FIG. 2, FIG. 3 is a procedure ofmigrating a virtual machine out of a level-2 resource pool. As shown inFIG. 3, a procedure 300 includes the following steps:

310. A user requests migration of a virtual machine 2 out of the level-2resource pool.

320. A system determines whether the number of physical cores in thelevel-2 resource pool needs to be reduced after the virtual machine 2 ismigrated out of the level-2 resource pool.

Each virtual machine in the level-2 resource pool is allowed to occupy50% of one physical core computing resource. Therefore, before thevirtual machine 2 is migrated out of the level-2 resource pool, if thenumber of virtual machines in the level-2 resource pool is an oddnumber, 50% of one physical core computing resource remains unallocatedin the level-2 resource pool. In this case, after the virtual machine 2is migrated out of the level-2 resource pool, one physical corecomputing resource is idle, and one physical core needs to be subtractedfrom the level-2 resource pool. On the contrary, before the virtualmachine 2 is migrated out of the level-2 resource pool, if the number ofthe virtual machines in the level-2 resource pool is an even number, thenumber of the physical cores in the level-2 resource pool cannot bereduced.

330. If the number of the physical cores in the level-2 resource poolneeds to be reduced, that is, when the number of the existing virtualmachines in the level-2 resource pool is an odd number, 50% of onephysical core computing resource remains unallocated in the level-2resource pool. In this case, after the virtual machine 2 is migrated outof the level-2 resource pool, one physical core computing resource isidle, and one physical core is allocated to the default resource pool,and the procedure skips to step 350.

340. If the number of the physical cores in the level-2 resource pooldoes not need to be reduced, the virtual machine 2 is migrated out ofthe level-2 resource pool.

350. The default resource pool adjusts allocation of physical corecomputing resources among virtual machines in the default resource poolcorrespondingly.

In the embodiment of the present invention, if all the virtual machinesin the level-2 resource pool are migrated out, all the physical cores inthe level-2 resource pool are allocated to the default resource pool.

The foregoing embodiment uses an example in which an advanced resourcepool includes a level-1 resource pool and a level-2 resource pool.Depending on an actual application scenario, the advanced resource poolmay include no such sub-resource pools as the level-1 resource pool andthe level-2 resource pool. Depending on an actual application scenario,the advanced resource pool may include not only the level-1 resourcepool and the level-2 resource pool, and a service level of eachsub-resource pool may be set according to the actual application.

According to the foregoing content, adjustment of the physical corecomputing resources in the default resource pool varies with specificsettings of the default resource pool. For example, if the virtualmachines in the default resource pool evenly share the computingresources of physical cores in the default resource pool, because onephysical core is added, a physical core computing resource that isallocated to each virtual machine in the default resource pool isincreased correspondingly, to fully use the physical core computingresources.

FIG. 4 is a signaling interworking diagram of a specific applicationscenario according to an embodiment of the present invention. Asdescribed in the application scenario shown in FIG. 4, a virtual machineis migrated from a source computing node to a destination computingnode. The method in the embodiment of the present invention, which isshown in FIG. 1, FIG. 2, and FIG. 3, may be applicable to theapplication scenario shown in FIG. 4.

As shown in FIG. 4, a migration process 400 includes the followingsteps:

410. A user sends a virtual machine migration request to a clustercontroller, requesting migration of a virtual machine 3 from the sourcecomputing node to the destination computing node.

420. The cluster controller receives the virtual machine migrationrequest sent by the user, and performs corresponding processing.

The cluster controller may perform corresponding processing according toa conventional virtual machine scheduling procedure, for example,preoccupying allocated resources.

430. The cluster controller sends a scheduling request to the sourcecomputing node, to migrate the virtual machine 3 out of the sourcecomputing node.

440. The virtual machine 3 is migrated out of the source computing node.

On the source computing node, for example, a virtual machinemigration-out procedure shown in FIG. 3 is performed.

450. The source computing node implements dynamic adjustment of physicalcore computing resources.

460. The virtual machine 3 is migrated into the destination computingnode.

On the destination computing node, for example, a virtual machinemigration-in procedure shown in FIG. 2 is performed.

470 .The destination computing node implements dynamic adjustment ofphysical core computing resources.

480. The source computing node returns a migration-out success orfailure message to the cluster controller.

490. The cluster controller notifies the user of a result of migrationof the virtual machine 3 from the source computing node to thedestination computing node.

According to the embodiment of the present invention, physical cores aredivided into different resource pools, and computing resources ofphysical cores in one resource pool are isolated from those in anotherresource pool, thereby implementing effective allocation of physicalcore computing resources for different application scenarios, avoidingappearance of a dominant virtual machine that occupies plenty ofcomputing resources, preventing imbalanced allocation of physical corecomputing resources, and improving efficiency of using computingresources of the physical cores.

The method in the embodiment of the present invention is applicable todifferent cloud computing business models. For example, in an Internetdata center (Internet Data Center, IDC for short) business model, avirtual machine located in a level-1 resource pool may be provided for auser, so that the virtual machine exclusively occupies one physical corecomputing resource at all time, and the computing resource will not beoccupied by another user, thereby providing a stable computingcapability for the user. For example, in a service private cloud(Service Private Cloud, SPC for short) business model, a virtual machineprovided for a user is required to have not only high performance andservice stability and but also a certain extent of CPU resource reuse.Therefore, virtual machines in both the level-1 resource pool and alevel-2 resource pool satisfy an application in such a scenario. Foranother example, in a virtual desktop infrastructure (Virtual DesktopInfrastructure, VDI for short) business model, a user requires a highprice/performance ratio of a virtual machine and reusability ofresources. In this case, the virtual machine has a high busy-to-idleratio, and virtual machines in a default resource pool are suitable forthe scenario.

An embodiment of the present invention further proposes a computing nodethat can apply the method in the embodiment of the present invention. Asshown in FIG. 5, a computing node 500 includes:

a resource adjusting unit 510, configured to adjust dynamically,according to a change in the number of virtual machines in an advancedresource pool, the number of allocated physical cores in the advancedresource pool, and adjust, according to the number of allocated physicalcores in the advanced resource pool, the number of allocated physicalcores in a default resource pool; and

a resource allocating unit 520, configured to divide physical cores of acentral processing unit into the default resource pool and the advancedresource pool according to service levels of the resource pools.

In this embodiment of the present invention, each resource pool servesvirtual machines that run in the resource pool. In a proper case, thecomputing node according to this embodiment of the present invention mayhave other technical features in the method embodiment of the presentinvention. The following uses examples to describe this.

According to the embodiment of the present invention, the service levelincludes the number of physical core computing resources that can beoccupied by each virtual machine.

According to the embodiment of the present invention, the resourceallocating unit 520 is configured to schedule virtual machines in thedefault resource pool to share computing resources of all the physicalcores in the default resource pool.

According to the embodiment of the present invention, the advancedresource pool includes a level-1 resource pool, where each virtualmachine in the level-1 resource pool is allowed to exclusively occupyone physical core computing resource.

According to the embodiment of the present invention, the advancedresource pool includes a level-2 resource pool, where each virtualmachine in the level-2 resource pool is allowed to occupy 50% of onephysical core computing resource.

According to the embodiment of the present invention, when the number ofthe virtual machines in the advanced resource pool increases, theresource adjusting unit 510 determines, according to the number ofincreased virtual machines and a service level of the advanced resourcepool, a first number of physical cores that need to be allocated to theadvanced resource pool, and allocates the first number of physical coresto the advanced resource pool from the default resource pool;

or

when the number of the virtual machines in the advanced resource pooldecreases, the resource adjusting unit 510 determines, according to thenumber of decreased virtual machines and a service level of the advancedresource pool, a second number of physical cores that need to besubtracted from the advanced resource pool, and allocates the secondnumber of physical cores to the default resource pool from the advancedresource pool.

According to the embodiment of the present invention, the resourceadjusting unit 520 is configured to allocate the physical cores in theadvanced resource pool to the default resource pool when no virtualmachine runs in the advanced resource pool.

As shown in FIG. 6, according to the embodiment of the presentinvention, the computing node 500 further includes:

a first determining unit 530, configured to determine that, after thenumber of the virtual machines in the advanced resource pool changes,the number of the physical cores in the advanced resource pool isinsufficient to satisfy the service level of the advanced resource pool.

According to the embodiment of the present invention, the firstdetermining unit 530 is further configured to determine that, when thenumber of the virtual machines in the advanced resource pool changes, atleast one idle physical core computing resource that does not serve avirtual machine in the advanced resource pool exists in the advancedresource pool.

According to the embodiment of the present invention, the resourceallocating unit 520 is configured to schedule the virtual machines inthe default resource pool to share computing resources of all thephysical cores in the default resource pool according to a presetpercentage of the physical core computing resources that can be occupiedby each virtual machine.

According to the embodiment of the present invention, the resourceadjusting unit 510 is configured to determine, according to the numberof the physical cores in the default resource pool and the presetpercentage of the physical core computing resources that can be occupiedby each virtual machine, the number of virtual machines that can beaccommodated by the default resource pool.

According to the embodiment of the present invention, the resourceallocating unit 520 is configured to schedule the virtual machines inthe default resource pool to evenly share computing resources of all thephysical cores in the default resource pool.

According to the embodiment of the present invention, the resourceallocating unit 520 is configured to set, for each virtual machine inthe default resource pool, an upper-limit percentage and/or alower-limit percentage of the physical core computing resources that canbe occupied by each virtual machine.

According to the embodiment of the present invention, the resourceallocating unit 520 is configured to set, for the virtual machines inthe default resource pool, a priority of each virtual machine in usingphysical core computing resources, and allocate physical core computingresources to the virtual machines in the default resource pool indescending order of priorities.

FIG. 7 is another schematic structural diagram of a computing nodeaccording to an embodiment of the present invention. As shown in FIG. 7,a computing node 700 includes at least one processor 710 such as a CPU,at least one port 720, a memory 730, and at least one communications bus740. The communications bus 740 is configured to implement connectionsand communication between these apparatuses. The processor 710 isconfigured to execute an executable module stored in the memory 730,such as a computer program. Optionally, the computing node includes auser interface 750, which includes but is not limited to a display, akeyboard, and a click device such as a mouse, a trackball (trackball), atouchpad, or a touchscreen. The memory 730 may include a high-speed RAMmemory, and may include a non-volatile memory (non-volatile memory),such as at least one magnetic disk memory. Communication connectionbetween the computing node and the cluster controller is implemented byusing the at least one port 720, and communication connection betweenthe computing node and at least one other computing node is implementedby using the at least one other port 720.

In some implementation manners, the memory 730 stores the followingelement, an executable module or a data structure, or a subset thereof,or an extension set thereof:

an operating system 732, including various system programs, which isconfigured to implement various basic services and processhardware-based tasks; and

an application module 734, including various applications, which isconfigured to implement various application services.

The application module 734 includes but is not limited to a resourceadjusting unit 510, a resource allocating unit 520, and a firstdetermining unit 530.

For specific implementation of the units in the application module 734reference may be made to corresponding units in the embodiments shown inFIG. 5 and FIG. 6, and details are not described herein again.

A person of ordinary skill in the art can be aware that the exemplaryunits and algorithm steps described with reference to the embodimentsdisclosed in this specification may be implemented by electronichardware or a combination of computer software and electronic hardware.Whether the functions are performed by hardware or software depends onparticular applications and design constraint conditions of thetechnical solutions. A person skilled in the art may use differentmethods to implement the described functions for each particularapplication, but it should not be considered that such implementationgoes beyond the scope of the present invention.

It can be clearly understood by a person skilled in the art that, forthe purpose of convenient and brief description, for a detailed workingprocess of the foregoing system, apparatus, and unit, reference may bemade to a corresponding process in the foregoing method embodiments, anddetails are not described herein again.

In the several embodiments provided in the present application, itshould be understood that the disclosed system, apparatus, and methodmay be implemented in other manners. For example, the describedapparatus embodiment is merely exemplary. For example, the division ofunits is merely a division of logical functions and there may be otherdivisions in actual implementation. For example, a plurality of units orcomponents may be combined or integrated into another system, or somefeatures may be ignored or not performed. In addition, the displayed ordiscussed mutual couplings or direct couplings or communicationconnections may be implemented through some interfaces. The indirectcouplings or communication connections between the apparatuses or unitsmay be implemented in electronic, mechanical, or other forms.

The units described as separate parts may be or not be physicallyseparate, and parts displayed as units may be or not be physical units,that is, the units may be located in one position, or may be distributedon a plurality of network units. A part or all of the units may beselected according to actual needs to achieve the objectives of thesolutions of the embodiments.

In addition, functional units in the embodiments of the presentinvention may be integrated into one processing unit, or each of theunits may exist alone physically, or two or more units are integratedinto one unit.

When the functions are implemented in a form of a software functionalunit and sold or used as an independent product, the functions may bestored in a computer-readable storage medium. Based on such anunderstanding, the technical solutions of the present inventionessentially, or the part contributing to the prior art, or a part of thetechnical solutions may be implemented in a form of a software product.The software product is stored in a storage medium, and includes severalinstructions for instructing a computer device (which may be a personalcomputer, a server, or a network device) to perform all or a part of thesteps of the methods described in the embodiments of the presentinvention. The foregoing storage medium includes: any medium that canstore program code, such as a USB flash drive, a removable hard disk, aread-only memory (ROM, Read-Only Memory), a random access memory (RAM,Random Access Memory), a magnetic disk, or an optical disc.

The foregoing descriptions are merely specific embodiments of thepresent invention, but are not intended to limit the protection scope ofthe present invention. Any variation or replacement readily figured outby a person skilled in the art within the technical scope disclosed inthe present invention shall fall within the protection scope of thepresent invention. Therefore, the protection scope of the presentinvention shall be subject to the protection scope of the claims.

What is claimed is:
 1. A method for allocating central processing unitresources of a computing node, wherein physical cores of the computingnode are pooled into an advanced resource pool and a default resourcepool, wherein the method is performed by the computing node, the methodcomprising: determining, according to a change in a number of virtualmachines that run in the advanced resource pool, a number of physicalcores that need to be adjusted between the advanced resource pool andthe default resource pool, wherein a virtual machine running in theadvance resource pool is allowed to occupy more physical core computingresources than a virtual machine running in the default resource pool;and adjusting, according to the number of physical cores that need to beadjusted, a number of physical cores for the virtual machines that runin the default resource pool; and adjusting, a lower limit of physicalcore computing resources occupied by each default virtual machine in thedefault resource pool based on the physical core adjusting operation inthe default resource pool.
 2. The method according to claim 1, whereinfurther comprising: determining that, after the number of the virtualmachines in the advanced resource pool changes, the number of thephysical cores in the advanced resource pool is insufficient to satisfythe requirements of the virtual machines that run in the advancedresource pool; allocating the first number of physical cores to theadvanced resource pool from the default resource pool.
 3. The methodaccording to claim 1, wherein further comprising: determining, accordingto the number of decreased virtual machines in the advanced resourcepool, a second number of physical cores that need to be subtracted fromthe advanced resource pool; and allocating the second number of physicalcores to the default resource pool from the advanced resource pool. 4.The method according to claim 3, wherein further comprising: determiningthat, after the number of the virtual machines in the advanced resourcepool changes, at least one idle physical core computing resource thatdoes not serve a virtual machine in the advanced resource pool exists inthe advanced resource pool.
 5. The method according to claim 1, whereinthe advanced resource pool comprises a level-1 resource pool and eachvirtual machine in the level-1 resource pool is allowed to exclusivelyoccupy one physical core computing resource.
 6. The method according toclaim 5, wherein the advanced resource pool comprises a level-2 resourcepool and each virtual machine in the level-2 resource pool is allowed tooccupy 50% of one physical core computing resource.
 7. The methodaccording to claim 1, further comprising: setting, for virtual machinesthat run in the default resource pool, an upper-limit percentage of thephysical core computing resources that can be occupied by each virtualmachine.
 8. The method according to claim 1, further comprising:setting, for virtual machines that run in the default resource pool, thelower-limit percentage of the physical core computing resources that canbe occupied by each virtual machine.
 9. A computing node for allocatingcentral processing unit resources to a virtual machine, wherein physicalcores of the computing node are pooled into an advanced resource pooland a default resource pool, the computing node comprising: a memorycomprising instructions; and one or more processors in communicationwith the memory and configured to execute the instructions to:determine, according to a change in the number of virtual machines thatrun in the advanced resource pool, a number of physical cores need to beadjusted between the advanced resource pool and the default resourcepool, wherein a virtual machine running in the advance resource pool isallowed to occupy more physical core computing resources than a virtualmachines running in the default resource pool; and adjust, according tothe number of physical cores that need to be adjusted, a number ofphysical cores for the virtual machines that run in the default resourcepool; and adjust, a lower limit of physical core computing resourcesoccupied by each default virtual machine in the default resource poolbased on the physical core adjusting operation in the default resourcepool.
 10. The computing node according to claim 9, wherein the one ormore processors execute the instructions to: determine that, after thenumber of the virtual machines in the advanced resource pool changes,the number of the physical cores in the advanced resource pool isinsufficient to satisfy the requirements of the virtual machines thatrun in the advanced resource pool; allocate the first number of physicalcores to the advanced resource pool from the default resource pool. 11.The computing node according to claim 9, wherein the one or moreprocessors execute the instructions to: determine, according to thenumber of decreased virtual machines in the advanced resource pool, asecond number of physical cores that need to be subtracted from theadvanced resource pool; and allocate the second number of physical coresto the default resource pool from the advanced resource pool.
 12. Thecomputing node according to claim 11, wherein the one or more processorsexecute the instructions to: determine that, after the number of thevirtual machines in the advanced resource pool changes, at least oneidle physical core computing resource that does not serve a virtualmachine in the advanced resource pool exists in the advanced resourcepool.
 13. The computing node according to claim 9, wherein the advancedresource pool comprises a level-1 resource pool and each virtual machinein the level-1 resource pool is allowed to exclusively occupy onephysical core computing resource.
 14. The computing node according toclaim 13, wherein the advanced resource pool comprises a level-2resource pool and each virtual machine in the level-2 resource pool isallowed to occupy 50% of one physical core computing resource.
 15. Thecomputing node according to claim 9, wherein the one or more processorsexecute the instructions to: set, for virtual machines that runs in thedefault resource pool, an upper-limit percentage of the physical corecomputing resources that can be occupied by each virtual machine. 16.The computing node according to claim 9, wherein the one or moreprocessors execute the instructions to: set, for virtual machines thatrun in the default resource pool, the lower-limit percentage of thephysical core computing resources that can be occupied by each virtualmachine.
 17. A nonvolatile computer readable storage medium comprisinginstructions that when executed by one or more processors of a computingnode, cause the one or more processors to: determine, according to achange in the number of virtual machines that run in an advancedresource pool, a number of physical cores need to be adjusted betweenthe advanced resource pool and a default resource pool, wherein physicalcores of the computing node are pooled into the advanced resource pooland the default resource pool, a virtual machine running in the advanceresource pool is allowed to occupy more physical core computingresources than a virtual machines running in the default resource pool;and adjust, according to the number of physical cores that need to beadjusted, a number of physical cores for the virtual machines that runin the default resource pool; adjust, a lower limit of physical corecomputing resources occupied by each default virtual machine in thedefault resource pool based on the physical core adjusting operation inthe default resource pool.
 18. The nonvolatile computer readable storagemedium according to claim 17, further comprising instructions that whenexecuted by one or more processors, cause the one or more processors to:determine that, after the number of the virtual machines in the advancedresource pool changes, the number of the physical cores in the advancedresource pool is insufficient to satisfy the requirements of the virtualmachines that run in the advanced resource pool; allocate the firstnumber of physical cores to the advanced resource pool from the defaultresource pool.
 19. The nonvolatile computer readable storage mediumaccording to claim 17, further comprising instructions that whenexecuted by one or more processors, cause the one or more processors to:determine, according to the number of decreased virtual machines in theadvanced resource pool, a second number of physical cores that need tobe subtracted from the advanced resource pool; and allocate the secondnumber of physical cores to the default resource pool from the advancedresource pool.
 20. The nonvolatile computer readable storage mediumaccording to claim 19, further comprising instructions that whenexecuted by one or more processors, cause the one or more processors to:determine that, after the number of the virtual machines in the advancedresource pool changes, at least one idle physical core computingresource that does not serve a virtual machine in the advanced resourcepool exists in the advanced resource pool.
 21. The nonvolatile computerreadable storage medium according to claim 17, further comprisinginstructions that when executed by one or more processors, cause the oneor more processors to: set, for virtual machines that runs in thedefault resource pool, an upper-limit percentage of the physical corecomputing resources that can be occupied by each virtual machine. 22.The nonvolatile computer readable storage medium according to claim 17,further comprising instructions that when executed by one or moreprocessors, cause the one or more processors to: set, for virtualmachines that run in the default resource pool, the lower-limitpercentage of the physical core computing resources that can be occupiedby each virtual machine.